The present invention is related to Japanese patent application No. 2000-148458, filed May 19, 2000; the contents of which are incorporated herein by reference.
The present invention relates to air volume control for an air conditioning system, and more particularly, to an air volume control for a vehicle with a convertible top.
Conventionally, in JP-A No. S63-41226, an air volume control in an air conditioning system for an open car is proposed. In this conventional art, when the car speed is increased during traveling with the vehicle roof open, the blowout air volume within a vehicle compartment is reduced. Air flowing around an occupant in an open roof car flows obliquely upward and rearward along an inclination of the vehicle wind shield and is a turbulent flow being entangled from forward to rearward of the vehicle. This entangling or entrapped air becomes stronger with vehicle speed.
However, in the conventional art described above, since the blowout air volume to the inside of a vehicle compartment is decreased during high speed traveling, an occupant is uncomfortable when exposed to the high temperature and strong entangling air during high speed traveling in hot summer. Also, the occupant is uncomfortable when exposed to the entangling air during the cold low temperatures of winter.
In view of the these and other drawbacks, the present invention provides a blowing means (4) for blowing air to inside a vehicle compartment, heat exchanging means (11, 13) for exchanging heat with air blown by the blowing means (4), a determining means (S52) for determining an opening/closing state of a roof (40), and air volume control means (S51, S53, S54, S55) for increasing air volume of the blowing means (4) according to an increase in a vehicle speed.
Accordingly, when the roof (40) is open, even if an airflow is entrapped from rearward to forward in the vehicle due to an increase in vehicle speed, poor air conditioning feeling due to entrapped air can be restrained by increasing blowout air volume.
In another aspect, a computing means (S4) for computing a target temperature (TAO) of air blown inside a vehicle compartment, wherein an air volume control means includes a reference air volume determining means (S51) for determining reference air volume based on a target temperature (TAO), and a correction air volume determining means (S53 S55) for determining correction air volume relative to the reference air volume in response to an increase in a vehicle speed when the determining means S52 has determined that the roof (40) is open. Accordingly, blowout air volume can be determined by correcting reference air volume determined based on the target temperature (TAO) according to the vehicle speed.
In another aspect, a determining temperature of an outside air temperature (Tam) is set as a first prescribed temperature (T1) for determining the lower limit of a range of the outside air temperature during spring or fall, such as spring or autumn, a second predetermined temperature (T2) for determining the upper limit of the outside air temperature range during spring or fall, wherein a determining means (S52) has determined that the roof (40) is open, and increasing air volume of a blowing means (4) according to an increase in vehicle speed when the outside air temperature (Tam) less than a first prescribed temperature (T1), and when the outside air temperature (Tam) greater than a second prescribed temperature (T2).
In an intermediate temperature area during spring or autumn, since the outside air temperature is comfortable, the poor air conditioning feeling due to entrapped air is slight. Thus, a correction of air volume according to the vehicle speed is conducted only during low outside air temperature (Tam less than T1) and high outside air temperature (Tam greater than T2) when the roof (40) is open. The correction of the air volume is not conducted according to the vehicle speed when the outside air temperature is in an intermediate temperature area (in range of T1-T2).
Only when the roof is opened during low and high outside air temperature, the air volume correction according to the vehicle speed is conducted to inhibit worsening of the air conditioning feeling. On the other hand, in an intermediate temperature area during spring and autumn, the correction of the air volume according to the vehicle speed is prohibited to stop unnecessarily increasing blowout air volume.
In another aspect, a blowing means (4) for blowing air toward inside a vehicle compartment, heat exchanging means (11, 13) for exchanging heat thereof with blowing air of the blowing means (4), a determining means (S52) for determining an opening/closing state of a roof (40), and air volume control means (S51, S53, S54, S55) for controlling air volume of the blowing means (4) is provided. As the determining temperature of the outside air temperature (Tam), a first prescribed temperature (T1) for determining the lower limit in a range of outside air temperatures during spring or fall, and a second prescribed temperature (T2) for determining the upper limit in a range of the outside air temperatures during spring or fall are set. Wherein, the determining means (S52) has determined the roof (40) is open. Further, when the outside air temperature (Tam) less than the first prescribed temperature (T1), and the outside air temperature (Tam) greater than the second prescribed temperature (T2), the air volume of the blowing means (4) is increased.
Only when the roof is opened during low outside air temperature and a high outside air temperature is an increase in air volume is conducted to inhibit worsening the air conditioning feeling. On the other hand, in an intermediate temperature area of spring and autumn, air volume correction is prohibited, and unnecessary air blowout increase is stopped.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are intended for purposes of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.